Posted
by
CmdrTacoon Tuesday October 12, 2010 @06:53PM
from the that's-not-so-hot dept.

sciencehabit better let Greg Dean know that "Two weeks ago, U.S.-based astronomers announced the discovery of the first Goldilocks planet circling another star: just the right size and just the right temperature to harbor alien life. But yesterday at an exoplanet meeting in Turin, Italy, Switzerland-based astronomers announced that they could find no trace of the prized planet in their observations of the same planetary system."

This is not a reasonable assumption. Our models are at best simplifications of reality. Do atoms *really* exist the way we envision them? Is there such a thing as an electron as a real finite particle? it wasn't that long ago that we believed that atoms were indivisible, discrete particles of matter. Our new models make that look ridiculously naive. 100 years from now I think it is likely that our current models will look ridiculously naive.

But older, naive models work fine for a lot of problems. We don't have to know how things *really* work at a low level as long as we can build a repeatable model that is useful for our tasks. The model can be (and almost certainly is) a black box with interfaces that we care about. Everything inside the box is up for grabs. Not knowing what is really going on inside doesn't affect our ability to solve our problem, so we ignore it (for now anyway).

The question you have to ask yourself is if the Universe can have a description which is isomorphic to reality, but still different. I suspect that there are several such descriptions. There are probably even an infinite number of such descriptions. Which is the correct one? If the descriptions are isomorphic, then it doesn't matter for our purposes what reality is. But a model that is isomorphic to reality is not the same as reality.

Why is this important? Because believing that science is true leads you into treating science as a religion. If you believe something is true, then you have a hard time changing it when it proves to be useful. Scientific models are meant to be useful. Assuming they are also true is very bad science.

This aspect of science is not taught enough. Science is only a model, but it is a fantastic and useful model and is constantly being made better. It seems to me that some people feel that using the word model to describe science is some sort of pejorative like the way the uneducated use the word "theory".

A scientific model is a mental conception of how something works. We all use models. For example, we might have a model in our minds of how a car works and use this model to make practical decisions about how to start the car on a cold morning. Our model doesn't have to be right to be useful. We may be totally wrong about how the engine works, but our model will probably be useful as long as we don't extend it too far. Of course, if we decide to rebuild our own carburetor, we might discover that our model is no longer adequate for our needs.

A scientific model need not be right, but it must be useful. That is, it must allow us to make useful predictions about how nature works. Scientists use models as mental crutches to help them think about nature. A chemist, for example, thinks of a molecule as little balls linked together with rods. Real molecules are much more complex than this model, but it is almost impossible to think about chemistry without using such a model to visualize molecular structure.

The astronomer's model of the celestial sphere is very helpful, and we can use it to think about the sun rising in the east and setting in the west. We can imagine the way the stars move across the sky, and we can predict the motion of the sky as a whole. Of course, the model is wrong, but as a mental aid to visualizing the motions in the sky, it is very useful within its limitations.

Some scientific models can be systems of mathematical equations expressed in computer programs that mimic the behavior of complex processes-an exploding star, for example. Our imaginations are not capable of numerical precision; such models act as mathematical crutches to help us "imagine" complicated processes with numerical precision.

Scientific models can range from general aids to visualization to mathematical equations that mimic the behaviors of complex systems. In every case, the model helps us think about nature. It doesn't have to be true, but as long as we don't press a model beyond its limitations, it can be tremendously useful. In a sense, scientists are not so much searching for ultimate truths as they are trying to build better and better models of how nature works.

Kind of arrogant, don't you think? That we humans, who just happen to be a bit smarter than chimps and capable of speech and writing, have somehow made a great leap that no other known creature has ever made: from modelling the world around us according to our abilities, to truly comprehending its fundamental nature in an absolute sense?

True, but he does have a point -- there are really no "hard rules of physical reality". A thousand years ago there was no such thing as electricity. A hundred years ago there were no such things as black holes. Before Einstein, the hard rule of physical reality was that time never changed, but now we know that speed changes time. We can have no idea what the "hard rules of physical reality" will be in a thousand years; science constantly discovers new rules of physical reality.

Sure they could-Assumption: They have the ability to cloak an entire planet.*Secondary assumption: With that level of technology, they likely have FTL communications and FTL travel.Therefore: They have spies here who passed our discovery of them to their home, thus causing their leaders to hide the planet.

*It is true, of course, that the secondary assumption does not necessarily follow from the first assumption, but we're guessing here anyway and it's a pretty reasonable assumption.

>*Secondary assumption: With that level of technology, they likely have FTL communications and FTL travel.

There is no reason why you need both. FTL travel is potentially a lot harder than FTL communications. At this stage we believe both to be probably impossible but we also have theories on how it may be possible to do both (the same theories applying to time travel actually). The thing is all the theories require energy and technologies which we are by no means certain are feasible. The one thing we ca

unless they've harnessed somehow harnessed the power of TQM (http://en.wikipedia.org/wiki/Transactional_interpretation) then they would have known in advance we'd be looking. I think. Qunatum stuff maes my head hurt.

Glad this story came up before we launched a probe for a 400,000 year flight. Wow would that have been a letdown.

It wouldn't take a probe 400 000 years. Gliese 581 is in our own back yard, a "mere" 20 light years away. A probe can accelerate all the way, and then radio its findings back as it flies past. Using pulsed plasma propulsion, it can probably be done in 3-4 centuries.

But, when something sounds to good to be true, it probably is. Whether it's a Nigerian president's widow wanting to share her fortune with you, a car that runs on water, or a Goldilocks planet in our own neighbourhood.Exceptional claims require exceptional evidence.

Yeah, now all you have to do is build a pulse plasma engine that can accelerate for several hundred years in deep space without malfunctioning and with little solar power available. As soon as you finish designing that, we'll get right on launching that probe.

I understand your point here, but I'm not sure this claim is exceptional. I think one of the points was that although this is the first (assuming it's true), this sort of thing is probably pretty common in the context of the size of the universe.

I got the estimate from a slashdot article [slashdot.org], though, I was off by a factor of about 2 (it is only 180,000 years). It was really just a reference to that article. But maybe you know how to build a ship that is 99.9% fuel and can do this. BTW, that 0.1% has to include the anti-mater fuel tank, the mater fuel tank, the thrusters, and the payload. Oh, and the fuel tanks can't consume any energy or require repair for 180,000 years.

You only need matter for the initial acceleration. Space isn't 100% vacuum, and going at high speeds, the problem is going to be too much matter.And of course the fuel tanks can consume energy. Why do you say they can't? Getting rid of energy is likely a bigger problem.

As for repairs, redundancy works well too. A high fault tolerance RAID (in this case, Redundant Array of Independent Drives), perhaps?

All in all, there are plenty of technical problems, but nothing that makes a speedy probe impossible. T

The only people who are calling it "habitable" are journalists who don't read what the scientists actually wrote.

It was supposed to be in the region where liquid water is capable of existing - that does NOT under any circumstances, immediately mean that it's "habitable". It means that there's a possibility of water being liquid - nothing more, nothing less. You can have a lot of situations where there's the possibility of there being liquid water, that are still completely not habitable.

Well it looks like the U.S. astronomers used two sets of data gathered from different time periods for their analysis. Meanwhile, the Swiss astronomers used a third set of data gathered over a different time period for their analysis. I would think the first thing that should be done would be to swap data sets. Have the U.S. astronomers run their analysis on the Swiss data set with their tools, and have the Swiss astronomers run their analysis on the U.S. data sets with their tools. After all is said and done, compare the results yielded by each data set. If only the U.S. astronomers are finding the gravitational wiggles, then it means that either their tools are inducing some kind of experimental error, or the Swiss tools are missing some critical component. At which point the tools and methods between the two groups should be compared and contrasted to observe differences.

If, however, U.S. analysis of the Swiss data sets similarly yields a no planet result, and Swiss analysis of U.S. data sets yields a planet exists result, then you can conclude that the problem is in the data, and not the analysis being done. So, the moral of the story to both teams is to send their data to each other. For bonus points, both parties can publish all of their data so that a few third parties can conduct their own analysis. This is what science is all about after all folks!

US astronomers used their published data (henceforth called 'A') and the Swiss published data (henceforth called 'B'). The Swiss used their published data B and their unpublished data (henceforth called 'C'). So we've tested A+B and B+C. We'll see what the deal is when we can do A+B+C...

And how will that help? We are talking about a planet on a orbit here. It's something constant. The woobling in the starts will be something periodic, and ALL THE TIME we are having a doppler shift of the radiation one way or another.

It will help because you can't claim that you've debunked another scientist's analysis until both analyses are appropriately filtered for possible human error, which, if I recall correctly, is the single most common cause if false conclusions in the scientific world.

Discovering new habitable planets while seemingly not researching ways to get us there is kind of like going to a whorehouse with no money. You usually end up very pissed off that all you could do is look.

Well you see the "getting us there" is just an aim that you picked out of the blue which bears no relationship to any objectively positive outcome, a generally accepted purpose, or a feasible construct. It makes just as much sense to say:

"Discovering new habitable planets while seemingly not researching ways to get me a ham sandwich is kind of like going to a whorehouse with no money. You usually end up very pissed off if you blood sugar gets too low.

Sounds like the plot of Peter F. Hamilton's novel Pandora's Star. Basically a Star being observed by an astronomer goes goes out suddenly, it turns out it was enveloped in a solar-system sized impenetrable black barrier. Some alien entity did so to wall-in a potentially dangerous civilization intent on expanding to other systems. In this case the planet may have been sealed off.

Now given this star system is 20 light years aware they must not have liked something they saw in our leaked radio or TV from 19

"Sir, about that planet, we've detected a flash of light [foxnews.com].""Captain, are you telling me they're testing nucular bombs?""No sir, just a flash of l--""Do you have any idea what the public will do when they discover the aliens are testing WMDs and we have no plan for dealing with them?""Sir, I was mistaken. There was no flash of light.""Not good enough, captain.""Sir, I was mistaken. There was no planet.""That's more like it."

The American team used a combined set of observations: One 11-year-long set consisted of 122 measurements made by the team, while the other set was 4.3 years long and consisted of 119 measurements published by the consortium.

[The Swiss group] used only their own observations, but they expanded their published data set from what the U.S. group included in its analysis to a length of 6.5 years and 180 measurements.

So, the American study had 241 observations over at least 11 years and the data is peer reviewed and published. The Swiss apparently are refuting that by ignoring half the data and adding 61 data points from 2.2 years that haven't been peer reviewed. Obviously they're a reputable group, but I'll wait for them to look at *all* of the data available to them, preferably published data, before just taking them at their word. Doubly so for a negative finding since alpha (chance of a false positive) tends to be a lot smaller than beta (chance of a false negative).

Consider the Swiss study to be a `peer review' of the American one. Peer review doesn't guarantee correctness in any case, it just guarantees the paper is in agreement with the views of a group of carefully selected others.

as all the "psychics" who "remote viewed" this new Earth-like planet, and regaled their little corners of the internet with tales of really tall humanoid shaped tree dwellers (yeah, go figure) will now have to back-pedal like mad.

He's been pretty successful at trolling on/. recently, getting lots of responses despite being both wildly off-topic and making no effort to disguise the trolling. Not posting as AC is apparently enough to get other users to respond to even obvious trolls.

Yeah I bet Vader wished he got one of those instead of that cool meeting room furniture and cool outfits for the gunners. If he wanted some bling he could have picked up a bitchin' performance muffler for the Death Star with proton-shielded baffles.

I wish the amount of letters someone could type in a reply was based on whether or not the person read anything past the head line. That I would never see this nonsense again. Not that i expect much from someone who calls themselves a 'windows expert'.

That's okay, after estimating that it has the right temperature and climate to support life, they forget the fact that life doesn't necessarily have to conform to the standards that happen to have come to be on Earth.

So we found this planet by measuring gravitational changes on light. If the planet were in fact cloaked, then wouldn't that be akin to just turning off the gravity for the whole planet? How could they keep everything from floating away? I guess this fancy pants alien technology is just too advanced for me to understand.

Don't underestimate the possibilities of mythical and theoretical equipment.

Look at Star Trek, since others have used that imaginary universe in this thread already. Cloaking shields to make a ship or planet disappear. Sure, perfectly rational. The ships in the Star Trek universe have gravity plating. If you can create it, you can negate it. Why not? The good old "suspension of disbelief" stands firm. But why stop there. What if the planet (if it was one) were in a tran

Well, moving the planet out of the solar system effectively hid it. Who looks for a habitable planetin interstellar space? The real question is there they got the trillions of stars to purchase the reactionless drives from the Outsiders that let them accelerate the 6 planets to.9c...

Earth's average temperature is 13c, 55f. So that planet would be pleasant near its equator. Near Earth's equator it's almost unbearably hot, near the poles is deadly cold. And I doubt a 37 day year would give you vertigo; does the Earth's 24 hour spin give you vertigo?

But it doesn't matter what its temperature is, curiosity will get us there eventually.